Expression And Function Of Plap-1 And Caveolin-1 In Periodontal Tissues And Cells Of Rat Orthodontic Tooth Movement Models

Objective: To investigate the expression of periodontal ligament-associated protein 1 (PLAP-1) and caveolin-1 in orthodontic tooth movement in rats and their roles in periodontal tissue reconstruction. Methods: Forty SD rats were randomly assigned to 4 groups of orthodontic tooth movements for 0, 3, 5, and 7 days, respectively. The controls and treatments were the first right and left maxillary molars without and with orthodontic pressure, respectively. After the treatments, the animals were sacrificed and periodontal tissues were collected to analyze gene expression using qRT-PCR and Western blot. The tissues were digested and cells were isolated to culture primary teeth cells. The cultured cells were induced to mineralize and assayed for expression of PLAP-1 and Caveolin-1 using Western blot. Results: Within 3 days after the orthodontic tooth movement, there was no significant difference in expression of PLAP-1 and Caveolin-1 between in the pressure side and control side (P > 0.05). On day 5, PLAP-1 was significantly upregulated in the pressure side as compared to the control side; on day 7, expression of PLAP-1 was downregulated and was significantly lower than that on day 3 (P < 0.05). For Caveolin-1, the expression was significantly up-regulated from day 3 as compared with the control (P < 0.01). In mineralizing cells, the expression of Caveolin-1 increased with the induction time; and the expression of PLAP-1 trended to increase two weeks after the induction and decreased afterward. In un-induced cells, the expression of the two genes did not changed with the culture time. Conclusion: In early orthodontic tooth movement, PLAP-1 was significantly up-regulated and then down-regulated with the increase in stimulation time, while the expression of Caveolin-1 constantly increased with treatment time, which is similar to what happen during the mineralization of cultured cells.